ok , 4 and 1/2 week old chicks going out today, how high should the heat lamp be off the ground and where should i put it ? , over the roosts , or just near the ground??? also we dont have much vetilation right now our coop is still in the making but for 9 4 and a 1/2 week old chicks how much do they need ?

Do you have a thermostat so you can put it under the light? That will tell you how high to put the lamp (ie: how warm it is under the lamp). You can pick one up at Target or Walmart for $1. Digital ones, which give you immediate readings cost about $8. Check in the reptile/pet section.

75-80F sounds like a good temperature. Make sure they have a space where they can get away from the heat if they want to.

Depending on how high your roost is, and what kind of chickens you have will determine if you should put it above the roost or at the floor. I'm going to guess that you should leave it on the floor until they're a little older.

Be careful with your ventilation. You don't want it getting too hot in there and cooking those little babies. Maybe you should wait to put them out until their coop is ready?